OVERLAPPING TERRITORIES BETWEEN THE THALAMOSTRIATAL AND NIGROTHALAMICPROJECTIONS IN CATS

FLUORESCENT tracers were injected into different regions of the caudat e nucleus and HRP-WGA in the substantia nigra of the cat in order to a nalyse the thalamic distribution of retrogradely labelled thalamostria tal neurones and anterogradely labelled nigrothalamic terminals within the thalamus. Overlapping thalamic territories between the thalamostr iatal neurones projecting to areas of the caudate nucleus and the nigr othalamic connections were observed in the rostral nuclei of the centr al thalamic group (ventral anterior nucleus, ventral anterior-ventral lateral complex and ventral medial nucleus) and, more restricted, in t he rostral (rhomboid, paracentral, ventral lateral, dorsal mediodorsal nuclei) and caudal intralaminar nuclei (centromedian-parafascicular c omplex). This study provides evidence of the existence of thalamic are as in which the input and output of the basal ganglia converge.